This invention relates to sprayers for leafy plants, in particular for use with plants that grow in rows on two or more wires extending between supporting stakes, for spraying thereon anti-frost liquids, chemicals or the like.
In viticulture, it is know to prevent frost-damage of vines either by covering vine-stock rows with plastic film, such as for example suggested in WO 97/03553, or by spraying the vine-stocks with water. The latter is normally performed by sprayers that are either mounted on hoses installed above the vine-stock rows or are attached to stakes supporting wires on which each row grows. The sprayers may also be installed on a machine, such as a vine-dressing machine described in U.S. Pat. No. 4,333,266, adapted to pass between the vine-stock rows.
In accordance with different aspects of the present invention, there are provided a novel method and a novel spraying assembly for spraying a liquid on plants, and also a novel sprayer holder for use therein.
The method, in accordance with one aspect of the present invention, includes the steps of:
(a) providing at least a pair of upper and lower wires parallel to each other and extending between wire-supporting stakes;
(b) providing at least one spraying assembly including a sprayer with at least one spraying nozzle and a sprayer holder with a rigid rod and upper and lower holder members mounted on said rod, one of said holder members having a sprayer seat for fixedly supporting said sprayer in a predetermined orientation relative to said rod;
(c) clamping said upper and lower members to the respective upper and lower wires in a predetermined orientation relative thereto so that, upon disposing said sprayer in said seat, said at least one nozzle faces the plants; and
(d) providing a fluid connection between said nozzle and a source of said liquid.
Another aspect of the present invention is connected with a spraying assembly for mounting a sprayer on a pair of upper and lower wires parallel to each other and extending between wire-supporting stakes. The assembly comprising a sprayer having at least one nozzle adapted for fluid connection with a source of said liquid, and a sprayer holder in the form of a rigid rod and upper and lower holder members mounted on said rod and having clamping means for being clamped to the respective upper and lower wires, one of said holder members having a sprayer seat for fixedly supporting said sprayer in a predetermined orientation relative to said rod.
Still another aspect of the present invention is connected with a holder for a sprayer having at least one nozzle, the holder comprising a rigid rod and upper and lower holder members mounted on said rod, one of said holder members having a sprayer seat for fixedly supporting said sprayer in a predetermined orientation relative to said rod. The holder is adapted for mounting on a pair of parallel wires and said upper and lower members have means for being clamped thereto.
When the sprayer assembly is mounted on two wires in accordance with the method of the present invention, the sprayer appears to be rigidly fixed in place in a required orientation relative to plants to be sprayed, due to the combined effect of the rigid rod and the clamping means of the upper and lower holder members.
Preferably, the method of the present invention is used for spraying plants such as, for example, vine-stacks, growing in a row on at least said upper and lower wires, where a plurality of assemblies of the present invention may be mounted between the wire supporting stakes. In this case, it is preferable that said sprayer has two nozzles facing in diametrically opposite directions perpendicular to an imaginary plane passing through said rod and a common vertical axis of the holder members. The sprayer assembly is then mounted on the upper and lower wires so that said imaginary plane is perpendicular thereto, whereby it is ensured that said nozzles are directed along said wires in two opposite directions.
Thus, the sprayer, when mounted in the sprayer holder of the present invention, may always be protected by the sprayer holder from any contact with agricultural machinery, such as vine-dressing machines. The sprayer is always kept in its fixed position relative to the row of vine-stacks, whereby any necessity of its adjustment is eliminated. The assembly has completely self-sufficient mounting means independent of the wire-supporting stakes and, therefore, a plurality of such assemblies may be mounted at any appropriate locations along the wires with any required pitch therebetween. The arrangement of the spraying assemblies on the wires enables them to follow any trajectory of plant rows, whereby any need in additional xe2x80x98compensatingxe2x80x99 sprayers is eliminated. The assembly is suitable for a range of diameters of the wires and is adapted for the adjustment to any distance between the wires.